Panic Hardware - 2017 NEC Changes

[LGreene]

There are some changes in the 2017 National Electrical Code with regard to rooms that require doors to have panic hardware or fire exit hardware. Since the NEC is not one of the codes I spend a lot of time reading, I'm hoping y'all can help me confirm whether I'm interpreting this correctly (or not).

Previous Edition:

The 2014 edition requires outswinging doors with listed panic hardware for doors intended for entrance/egress and located within 25 feet of the required working space, where any of the following are true:

• Where equipment is 600 volts or less and 800 amps or more and contains overcurrent devices, switching devices, or control devices (110.26 (C) (3))
  
• Where equipment is 600 volts or more (110.33 (A) (3))*
• Battery rooms (480.9 (E))

The 2014 edition states the following requirement for electrical vaults (110.31 (A)), transformer vaults (450.43 (C))*, and modular data centers (646.19): “Personnel doors shall swing out and be equipped with panic bars, pressure plates, or other devices that are normally latched but that open under simple pressure,” but if the rooms exceed the voltage/amperage levels above, listed panic hardware is required (not just any device that opens under simple pressure).

New Edition:

In the 2017 edition, outswinging doors with listed panic hardware are required for doors intended for entrance/egress and located within 25 feet of the required working space, where any of the following are true:

• Where equipment is 1000 volts or less and 800 amps or more and contains overcurrent devices, switching devices, or control devices (110.26 (C) (3))
  
• Where equipment is 1000 volts or more (110.33 (A) (3))*
• Transformer vaults (450.43 (C))*
  
• Battery rooms (480.10 (E))
• Energy storage systems (706.10 (D))

Doors intended for entrance/egress from working space in modular data centers with equipment over 1.8 m (6 ft) wide or deep must be outswinging doors equipped with panic bars, pressure plates, or other devices that are normally latched but open under simple pressure. (646.19)

* The NEC also requires these doors to be kept locked, with access allowed only to qualified persons.

Did I miss anything? Do any of you have insight into why the voltage limit went from 600 volts to 1000 volts? That seems like a pretty big jump.

Thanks in advance for your help!

 

[cda]

Do you have a NEC section reference:::



May not be in here

https://ez-ce.com/wp-content/uploads/2017-NEC-Significant-Code-Changes-Part-3-Wisconsin-preview.pdf

 

[Builder Bob]

Not an electrician or an engineer, but I did stay at the holiday express last night.....

I believe this has to do more with alignment of the traditional separation of low voltage and high voltage as defined or delineated in the NEC. Low Voltage in the NEC typically refers to line voltage of 1000 volts or less....., high voltage is above 1000 volts. See delineation in definitions for example - Part I 1000 volt or less, Part II over 1000 volts.

Slang or layman terms of low voltages tends to be identified with 12, 18, or 24 volts DC or AC especially in control voltage wiring.

Interestingly, 800 amp at 240 volts ac is 192000 volt amps or watts;

At 144000 volts ( low end transmission line voltage), this equates to 13.3333 amps.

This equates to a large reduction in amperage rating requirement for over current protection,

Thus the reason for the section above requiring panic hardware of voltage less than 1000 volts and over 800 amps; Or
over 1000 volts period

Article 110.26 (3) for less than 1000 volts (Part II - 1000 volts or less)

Article 110.33 Above 1000 volts. (Part III - Over 1000 volts)

 

[Builder Bob]

For clarification - the article numbers above are for the listed exit device that is referenced in the original question. This does not include all segments of the NEC where listed exit devices may be required, but specifically in reference to over current devices.

 

[cda]

No explanation for the change:::


https://www.mikeholt.com/instructor2/img/product/pdf/17BK-1474-sample.pdf

 

[Francis Vineyard]

. . . Did I miss anything? Do any of you have insight into why the voltage limit went from 600 volts to 1000 volts? That seems like a pretty big jump.
Thanks in advance for your help!

With the ever changing technology that is presented to the electrical industry, along came wind generation and photovoltaic (PV) systems. The High Voltage Task Group submitted more than 100 proposals for the 2014 NEC to raise the threshold from 600 volts to 1,000 volts in an attempt to keep up with the technological advancement in these technologies. Many PV systems are over 600 volts and the NEC lacked requirements to safely cover these systems. The 600-volt threshold had really never been an issue until the demand and need for sustainable energy resources technology expansion over the recent years. Increasing the voltage threshold alone will not completely cover these systems; however, it does provide a starting point for manufacturers.

http://www.ieci.org/newsroom-and-insights/600-volts-to-1000-volts


The NEC Correlating Committee understands that these revisions are necessary as the industry is evolving; however, it concedes this project is extensive and will extend into the 2017 NEC cycle and perhaps beyond. The assigned High Voltage Task Group also continues to be active in incorporating many other new medium- and high-voltage requirements throughout the NEC to close gaps and incorporate adequate NEC provisions for installations and systems that no longer are governed by the National Electrical Safety Code (NESC) or applicable utility regulations. The NEC does not typically cover wiring and equipment installed on the line side of the service point; it usually covers installations on the load side of the service point.

http://www.ecmag.com/section/codes-standards/2014-nec-outlook

 

[TheCommish]

So what or why in the sustainable technology kept the designers or engineers from staying under 600 volts